GBE - Revision history

Onion at 06:57, 8 October 2010

2010-10-08T06:57:24Z

Macallan: Replace outdated links regarding crime support on NetBSD with more up to date ones.

2009-04-30T16:35:04Z

Replace outdated links regarding crime support on NetBSD with more up to date ones.

Onion: /* Accessing GBE */

2008-07-24T08:02:11Z

‎Accessing GBE

Onion: Mention NetBSD accelerated console and X on O2

2008-03-14T22:47:33Z

Mention NetBSD accelerated console and X on O2

Onion: Link to a visws page

2005-02-17T08:31:56Z

Link to a visws page

Onion: Add GBE page

2005-02-14T10:51:39Z

Add GBE page

New page

== What is GBE? ==
GBE is the Grahics Back End on the SGI O2 and the SGI Visual Workstations. GBE transfers
image data from main memory to the attached display and also handles tasks like
display resolution, depth and palette.

== Accessing GBE ==
GBE is located at 0x16000000 on the O2 and at 0xd0000000 on the visws.

== How GBE works ==
(Text from the Linux driver)

The GBE hardware uses a tiled memory to screen mapping. Tiles are
blocks of 512x128, 256x128 or 128x128 pixels, respectively for 8bit,
16bit and 32 bit modes (64 kB). They cover the screen with partial
tiles on the right and/or bottom of the screen if needed.

Tiles have the advantage that they can be allocated individually in
memory. However, this mapping is not linear at all, which is not
really convienient. In order to support linear addressing, the GBE
DMA hardware is fooled into thinking the screen is only one tile
large and but has a greater height, so that the DMA transfer covers
the same region.
Tiles are still allocated as independent chunks of 64KB of
continuous physical memory and remapped so that the kernel sees the
framebuffer as a continuous virtual memory.

== Linux support ==
Framebuffer support with GBE is working fine under Linux.

← Older revision		Revision as of 06:57, 8 October 2010
Line 30:		Line 30:
	=== Acceleration ===		=== Acceleration ===
	The Linux driver does not support any kind of acceleration. Lately, NetBSD has gained acceleration support for both console [http://mail-index.netbsd.org/port-sgimips/2008/02/05/msg000066.html] and X [http://my.opera.com/Macallan/blog/2009/04/01/xorg-on-o2], [http://mail-index.netbsd.org/port-sgimips/2009/02/24/msg000437.html]. This information could be used for Linux too.		The Linux driver does not support any kind of acceleration. Lately, NetBSD has gained acceleration support for both console [http://mail-index.netbsd.org/port-sgimips/2008/02/05/msg000066.html] and X [http://my.opera.com/Macallan/blog/2009/04/01/xorg-on-o2], [http://mail-index.netbsd.org/port-sgimips/2009/02/24/msg000437.html]. This information could be used for Linux too.
		+
		+	[[Category:SGI]]

← Older revision		Revision as of 16:35, 30 April 2009
Line 29:		Line 29:

	=== Acceleration ===		=== Acceleration ===
−	The Linux driver does not support any kind of acceleration. Lately, NetBSD has gained acceleration support for both console [http://mail-index.netbsd.org/port-sgimips/2008/02/05/msg000066.html] and X [http://~~mail-index~~.~~netbsd~~.~~org~~/~~port-sgimips~~/~~2008~~/03/02/~~msg000107.html~~], [http://mail-index.netbsd.org/port-sgimips/~~2008~~/03/11/~~msg000148~~.html]. This information could be used for Linux too.	+	The Linux driver does not support any kind of acceleration. Lately, NetBSD has gained acceleration support for both console [http://mail-index.netbsd.org/port-sgimips/2008/02/05/msg000066.html] and X [http://my.opera.com/Macallan/blog/2009/04/01/xorg-on-o2], [http://mail-index.netbsd.org/port-sgimips/2009/02/24/msg000437.html]. This information could be used for Linux too.

← Older revision		Revision as of 22:47, 14 March 2008
Line 26:		Line 26:

	== Linux support ==		== Linux support ==
−	Framebuffer support with GBE is working fine under Linux.	+	Framebuffer (dumb) support with GBE is working fine under Linux.
		+
		+	=== Acceleration ===
		+	The Linux driver does not support any kind of acceleration. Lately, NetBSD has gained acceleration support for both console [http://mail-index.netbsd.org/port-sgimips/2008/02/05/msg000066.html] and X [http://mail-index.netbsd.org/port-sgimips/2008/03/02/msg000107.html], [http://mail-index.netbsd.org/port-sgimips/2008/03/11/msg000148.html]. This information could be used for Linux too.

@@ Line 4: / Line 4: @@
 display resolution, depth and palette.
-== Accessing GBE ==
+==Accessing GBE==
-GBE is located at 0x16000000 on the O2 and at 0xd0000000 on the visws.
+GBE is located at 0x16000000 on the SGI O2 and at 0xd0000000 on the SGI Visual Workstation.
 == How GBE works ==

@@ Line 1: / Line 1: @@
 == What is GBE? ==
-GBE is the Grahics Back End on the SGI O2 and the SGI Visual Workstations. GBE transfers
+GBE is the Grahics Back End on the SGI O2 and the [http://linux-visws.sourceforge.net/ SGI Visual Workstations]. GBE transfers
 image data from main memory to the attached display and also handles tasks like
 display resolution, depth and palette.